4
41
Guest
Sandy wrote:
> Dans le message de
> news:[email protected],
> 41 <[email protected]> a réfléchi, et puis a déclaré :
> > Sandy wrote:
> >> Dans le message de
> >> news:[email protected],
> >> 41 <[email protected]> a réfléchi, et puis a déclaré :
> >>
> >>> even without any
> >>> helmet, you will sustain a mortal injury to your brain before your
> >>> skull fractures.
> >>
> >> You may want to think about that, again.
> >
> > Or you. The original head injury standards for helmets were based on
> > prevention of skull fractures and those were 500 G. With the move to
> > the prevention of brain injury instead that went down to the 300 G
> > that we still see in today's Snell standards.
> >
> > <http://www.smf.org/articles/helmet_development.html>
>
> OR
>
> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1443374&dopt=Abstract
>
> http://www.emedicine.com/emerg/byname/epidural-hematoma.htm
>
> http://depts.washington.edu/hiprc/practices/topic/bicycles/helmeteffect.html
>
> Take a look again at what you wrote. It's not a sin to see it may be far
> from the truth.
No, you first. The references you supplied show you (a) did not read
what I wrote and (b) do not understand the problem, AT ALL. The first
two are entirely irrelevant and the third, containing capsule summaries
of other studies, might only possibly be relevant (in fact, those
studies do not have the detail necessary to know). You seem to think I
(a) said it was impossible to have a skull fracture without first
dying, and (b) that it is impossible to have a skull fracture from a
deceleration injury without dying. Indeed you might get that impression
from just the part you snipped out. The first mis-reading shows a
complete misunderstanding of the entire problem, the second shows an
only somewhat more refined misunderstanding of the entire problem.
Hint: read e.g. the Snell standards, FULLY. And why not, what I wrote
as well, noting what parts of those Snell standards I do and do not
refer to:
#> If had landed square on
#> the top right side of my head without my helmet, I probably would
have
#> fractured my skull. I believe that because I separated my shoulder,
#> and it hit second.
#It's hard to see how that would have happened without your brain
being
#scrambled first. At the 300g deceleration against a flat surace, you
#are not supposed to be at the limit of skull fracture, but you are
#supposed to be at the limit of brain scrambling. In other words, by
the
#time a bicycle helmet (as opposed to a hard hat) is protecting you
#against skull fracture, you are already dead, i.e., even without any
#helmet, you will sustain a mortal injury to your brain before your
#skull fractures. That is not the case if it is you who is at rest and
#the object that is flying against you, because in that case, your
#deceleration is 0g no matter what, comfortably below the 300g limit.
#But that is not what bicycle helmets are designed for.
> Dans le message de
> news:[email protected],
> 41 <[email protected]> a réfléchi, et puis a déclaré :
> > Sandy wrote:
> >> Dans le message de
> >> news:[email protected],
> >> 41 <[email protected]> a réfléchi, et puis a déclaré :
> >>
> >>> even without any
> >>> helmet, you will sustain a mortal injury to your brain before your
> >>> skull fractures.
> >>
> >> You may want to think about that, again.
> >
> > Or you. The original head injury standards for helmets were based on
> > prevention of skull fractures and those were 500 G. With the move to
> > the prevention of brain injury instead that went down to the 300 G
> > that we still see in today's Snell standards.
> >
> > <http://www.smf.org/articles/helmet_development.html>
>
> OR
>
> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1443374&dopt=Abstract
>
> http://www.emedicine.com/emerg/byname/epidural-hematoma.htm
>
> http://depts.washington.edu/hiprc/practices/topic/bicycles/helmeteffect.html
>
> Take a look again at what you wrote. It's not a sin to see it may be far
> from the truth.
No, you first. The references you supplied show you (a) did not read
what I wrote and (b) do not understand the problem, AT ALL. The first
two are entirely irrelevant and the third, containing capsule summaries
of other studies, might only possibly be relevant (in fact, those
studies do not have the detail necessary to know). You seem to think I
(a) said it was impossible to have a skull fracture without first
dying, and (b) that it is impossible to have a skull fracture from a
deceleration injury without dying. Indeed you might get that impression
from just the part you snipped out. The first mis-reading shows a
complete misunderstanding of the entire problem, the second shows an
only somewhat more refined misunderstanding of the entire problem.
Hint: read e.g. the Snell standards, FULLY. And why not, what I wrote
as well, noting what parts of those Snell standards I do and do not
refer to:
#> If had landed square on
#> the top right side of my head without my helmet, I probably would
have
#> fractured my skull. I believe that because I separated my shoulder,
#> and it hit second.
#It's hard to see how that would have happened without your brain
being
#scrambled first. At the 300g deceleration against a flat surace, you
#are not supposed to be at the limit of skull fracture, but you are
#supposed to be at the limit of brain scrambling. In other words, by
the
#time a bicycle helmet (as opposed to a hard hat) is protecting you
#against skull fracture, you are already dead, i.e., even without any
#helmet, you will sustain a mortal injury to your brain before your
#skull fractures. That is not the case if it is you who is at rest and
#the object that is flying against you, because in that case, your
#deceleration is 0g no matter what, comfortably below the 300g limit.
#But that is not what bicycle helmets are designed for.